Fans of The Simpsons may recall an episode in which Homer, inspired by his hero Thomas Edison, decides to become an inventor himself. Among his questionable creations is an electric hammer. Well, German DIY-guy Patrick Priebe recently took a break from building laser weapons, to make a real-life version of that hammer which actually works ... sort of.
The electric hammer is powered by an 18.5-volt, 3,000-mAh lithium-polymer battery, and is built from scratch mainly out of aluminum.
Depressing its wooden trigger activates an electromagnetic coil, which quickly draws in a cylindrical steel core. That core is attached to the bottom of a fiberglass rod, which shoots upwards as the core goes through the coil. Via a linkage, that rod subsequently thrusts the hammer's hinged head down and forward in an arc. Once the trigger is released, a spring pulls the rod/core back down again.
As can be seen in the following video, the finished product does indeed save the user from having to draw their arm back on each strike. Given the short distance that the head travels, however, it doesn't look like the hammer would be particularly effective on anything larger than small finishing nails ... which is probably why Homer carelessly left his behind at the Edison Museum.
Source: Laser Gadgets by Patrick Priebe